Semi-structured meshes for axial turbomachinery blades

Authors

  • L. Sbardella,

    1. Imperial College of Science, Technology and Medicine, Mechanical Engineering Department, Exhibition Road, London SW7 2BX, U.K.
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  • A. I. Sayma,

    1. Imperial College of Science, Technology and Medicine, Mechanical Engineering Department, Exhibition Road, London SW7 2BX, U.K.
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  • M. Imregun

    Corresponding author
    1. Imperial College of Science, Technology and Medicine, Mechanical Engineering Department, Exhibition Road, London SW7 2BX, U.K.
    • Mechanical Engineering Department, Imperial College of Science, Technology and Medicine, Exhibition Road, London SW7 2BX, U.K
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Abstract

This paper describes the development and application of a novel mesh generator for the flow analysis of turbomachinery blades. The proposed method uses a combination of structured and unstructured meshes, the former in the radial direction and the latter in the axial and tangential directions, in order to exploit the fact that blade-like structures are not strongly three-dimensional since the radial variation is usually small. The proposed semi-structured mesh formulation was found to have a number of advantages over its structured counterparts. There is a significant improvement in the smoothness of the grid spacing and also in capturing particular aspects of the blade passage geometry. It was also found that the leading- and trailing-edge regions could be discretized without generating superfluous points in the far field, and that further refinements of the mesh to capture wake and shock effects were relatively easy to implement. The capability of the method is demonstrated in the case of a transonic fan blade for which the steady state flow is predicted using both structured and semi-structured meshes. A totally unstructured mesh is also generated for the same geometry to illustrate the disadvantages of using such an approach for turbomachinery blades. Copyright © 2000 John Wiley & Sons, Ltd.

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